dpal: Create divergent color palettes using the HCL color space

In MichaelMalick/r-chroma: chroma

Description

dpal creates divergent color palettes using the HCL color space. Divergent color palettes consist of a gradient that goes from dark to light to dark where both ends of the gradient are a separate hue. Divergent color palettes are suitable when low and high values are of importance, but middle range values are less important.

Usage

dpal(n, hue = c(260, 0), chroma = 80, luminance = c(25, 100),
  power = 1.3, alpha = 1, fixup = TRUE)

Arguments

n	number of colors to create
hue	vector of length 2 giving the first and second hues to use
chroma	chroma value for palette
luminance	vector of length 2 giving the start and end bounds for the range of luminance values
power	parameter to control how chroma and luminance increase/decrease
alpha	transparency level defined on the interval [0, 1] where 0 = transparent and 1 = opaque
fixup	logical, should RGB value be corrected (see hcl

Value

dpal returns a vector of hex colors

Author(s)

Michael Malick

See Also

hcl qpal spal

Examples

plotpal(dpal(200))
plotpal(dpal(200, luminance = c(30, 90)))
plotpal(dpal(200, luminance = c(30, 90), power = 2))
plotpal(dpal(200, luminance = c(30, 90), power = 0.8))
plotpal(dpal(200, hue = c(100, 240)))
plotpal(dpal(200, hue = c(40, 240), luminance = c(30, 90)))

mat <- matrix(c(rnorm(100), rnorm(100) + 1, rnorm(100) + 2,
    rnorm(100) + 3),
              ncol = 4)
image(z = mat, col = dpal(200), axes = FALSE)
box()

MichaelMalick/r-chroma documentation built on May 7, 2019, 4:56 p.m.